Correlation Between Retinopathy Due To Type 2 Diabetes Mellitus And Cystatin C

Objective:Diabetes mellitus(DM) is a chronic metabolic disease with high blood sugar a feature, the pathogenesis is mainly caused by insulin resistance and(or) the lack of insulin, caused by a combination of many factors such as heredity、environment, is one of the major chronic diseases that is threatening the health of human. Among them, type 2 diabetes mellitus(T2DM) is the main type, and the microvascular complications of T2 DM are the leading cause of death and disability, not only seriously threading the health of human but also bringing heavy burden to the society. The diabetic retinopathy(DR) is one of the most common microvascular complications of diabetes patients, ultimately leads to irreversible blindness, which is also one of the most main risk factor leading to blindness among adults. So the early prevention 、diagnosis and effective treatment are very important for diabetes patients. Cystatin C(Cys C) belongs to the cysteine protease inhibitors, some studies have reported that Cys C is one of the independent risk factors for early diabetic nephropathy patients. DR and diabetic nephropathy are microvascular complications of diabetes patients, they are associated on pathogenesis.In recent years, studies have shown that Cys C also expressed in cells of rat retina and glass, but the correlation between Cys C and diabetic retinopathy in type2 diabetic patients had been less reported.We investigated the relationship between Cys C and DR in type2 diabetic patients, to find effective biological indicators that are important on the early prevention, timely diagnosis and treatment, evaluation for diabetic retinopathy in type2 diabetic patients.Methods:The total of 128 patients with T2 DM in the endocrine department of China-Japan Union Hospital of Jilin University from October 2013 to November 2015 were recruited, we carefully ask their medical history and related information, record test results, we undertaken fundus photography for all patients. All patients has been divided into two groups, non-diabetic retinopathy(NDR) and DR according to the publication of Diabetes diagnosis and classification standard of international diabetic retinopathy in 2002 and the results of fundus photography. DR group consists of non-proliferative diabetic retinopathy(NPDR) and proliferative diabetic retinopathy(PDR). Using immune turbidimetry to measure their plasma levels of Cys C, all the patients were also divided into four groups of Q1 to Q4 according to the Cys C concentrations quartiles. All the data processing using SPSS 18.0 statistical analysis software. Normally distributed measuring datas are showed by`x±s, compared between groups with analysis of variance;non-normal distribution ones are showed by M(P25-P75), with rank sum test. The comparison of rate by chi-square test. The correlation between research data by spearman. The related risk factors for DR by Logistic. According to the P<0.05 is defined that there is statistical significance. Results:1.The comparison results of general data and blood biochemical indexes in NDR、NPDR and PDR groups are show that: duration, Cys C, FPG, Hb A1 C, BUN, Cr, SBP have statistically significant between three groups(P<0.01). In contrast, the age, DBP, BMI, TC, TG, LDL, HDL, C-P, 2h C-P have no ifference between them(P>0.05).2.Compared with Q1 to Q3,high serum levels of Cys C group(Q4) has the high prealence of PDR, the difference was statistically significant(P<0.01).3.Spearman correlation analysis suggested that the level of Cys C are proportional to age, duration, Hb A1 C, Cr and BUN( respectively r=0.437, r=0.335, r=0.226, r=0.384, r=0.336;P<0.05 or P<0.01), the level of Cys C are negative correlation to BMI、SBP、DBP、FPG、TC、TG、HDL、LDL、C-P、2h C-P.4.Logistic multivariate regression analysis results: take whether have retinopathy as the dependent variable, take Cys C、diabetes duration Hb A1 C, FPG, Cr, BUN, SBP as independent variable,and then conduct the regression analysis. The results show that Cys C、Hb A1C、diabetes duration are the independent risk factors for diabetic retinopathy. Conclusion:1.The level of serum cystatin C is the independent risk factors for diabetic retinopathy in type 2 diabetic patients.2.The changes of the level of serum cystatin C may have a guiding significance in prevention, early diagnosis, Condition assessment for diabetic retinopathy in type 2 diabetic patients.